Motor crane underframe



Sept. 29, 1953 W. M. SHEEHAN MOTOR CRANE UNDERFRAME 3 Sheets-Sheet 1 Filed Jan. 9, 1950 I'll-all hm 6y p 1953 w. M. SHEEHAN 2,653,829

' MOTOR CRANE UNDERFRAME Sept. 29, 1953 w. M. SHEEHAN MOTOR CRANE UNDERFRAME 3 Sheets-Sheet 3 Filed Jan. 9, 1950 VIII lII/II/IIIIIII/IIII FIG. 8-.

FIG. IO.

Patented Sept. 29, 1953 UNITED STATES PATENT OFFICE MOTOR CRANE UNDERFRAME William M. Sheehan-,. Philadelphia, Pa, assig-nor' to General Steel Castings (Jooperation, v Granite City, Ill.,- a. corporation of Delaware.

Application January 9, 1950', Seri'al No.- 1 37505 9: Claims. 1-.

The invention relates to cranes oi. the type; in which an elongated boom is pivotally mounted at one. end on a movable frame. from which it may be extended in. difierent directions a substantial distance beyond the frame. in any desired.- direction. The frame may bev a: pamtofi' the chassis of' a vehicle adapted to travel over ordinar highways;

The invention. lies primarily in the frame. on which the boom and. its manipulating mechanism is mounted, and the invention consistsiir a; frame structure. formed. or a one piece casting: including' major sections extending transversely of: each other and so.- merging: with each: other and. so proportional} that: they will.- carry the. necessary loads and. resist the torsional; other stresses to which: the frame may be subjected without undue weight; of. metal. or reduction of strength required; for. relatively movable operating parts;

One object. of the invention is to avoid; the Laborand additional. materialrequired forbuilding up; a frame of. structural: shapesa which must be specially formed and; welded. or riveted; together...

Another object. is to construct a frame which will be lighter than one built up of structural steel and having a corresponding: size and strength". With; the current. and prospective restrictions on. permissible Wheel. loads on high-.- ways, minimum. weight is. extremely essential,

Another object is: to-simplify the assembly with the frame: of a turntable for. mounting the boom and its actuating. engine, and". fonmounting: out riggers for stabilizing, the crane while in-. operation.

In the accompanying drawings illustrating a; selectedembodi-mentiof the invention,

Figure 1 is a. side view, largely diagrammatic of a complete crane unit embodying. the frame forming the subject matter of the; present invention and. other. chassis. parts and the caband boom. structure mounted thereon.

Figure 2.. is in part atop viewof the chassis frame and in part a horizontal. section. taken: on the. line 2..-410i. Figure 4.

Figure 3 is a side View of the frame shown in Figure 2'.

Figure 4-. i in. part av viewlooking at the right hand end. of the frame shown in Figures 2;" and 3. and. in. part a. vertical section. taken uponthe line 4 -L of Figure 2.

Figures 5, 6, and are. transverse vertical sections takenon the corresponding section lines of. Figure 2..

Figure 7: is a. detailed. transverse section: look.-

2. ing in the opposite direction and: taken. on the line 'If-l of. Figure Figure 8 is a. detailed. section extendingilon'gi tudiim-lly of theframe and taken on. the:1inet 88 oiEig-ure 7..

9 a. detailed. longitudinal vertical section taken. on the line S--9'- of Figure 2..

The frame If is mounted. upon. a plurality of wheeled axles 2;, 3*, and 4. and. mounts a drivers Cab-551183.11 forward end, a turntable structure 6 and; anioperatcrfs cab T near'its. rear end; The crane boom 8: is pivoted. at 9: to: the turntable.

The chassis frame includes two main longitudinal. members; each consisting oi; a. relatively heavy rear: portion. and. a relatively lightforward portion. The relatively heavy rear portions l0 and H- are of. hos: shape cross section (Figures 5;, 6,, and 7 andthe relatively light forward portions: 1:2 and I131 are-of. channel shape cross section. (Figure-l0 Transverse members M I5, "51. thand 18 connect the main longitudinal members. Transverse members It and I! are of. box: shape cross; sectionand transversemembers- #5 are. of channel cross section; Transverse" member I 5 of in.- verted. T section. Forward transverse member l8 isof angular section: with; a horizontal web uniting; the upper portions of forward members 12 and t3.

Transverse members.-v H; W are substantially deeper. than longitudinal-members, "1;, I51 and: pject a substantial distance outwardly from the main longitudinal members L0,. H and form box section housings for outriggerindicated at l9, which. may be retracteddurine. crane: travel: and projected. during crane use. A heavy horizontal webazll; circular incontour, mergeswith the top walls of longitudinal members H), H. and. forms a platformifor the turntable 6.

Box. section. brackets 21 extend. downwardly froinmain. longitudinal members HI, I t adjacent the-rearot circular web 20 and include integral cylindrical bearings. 21 for journaling trunnions on equalizing, bars B- which mount rear wheel axles it and 4.. Brackets 2:3; depend. from for ward portion t2 and. I a-of-the main longitudinal members to suspend the shackles for'leaf. springs 24 which support the front end of the'trameron axle 2.

Wherethe main longitudinal members: [0 It and transverse members M, H intersect. their upright. webs merge in: curved: sections 25;. The top. Walls of the intersecting, members merge in gusset like sections 26". The bottom; walls Ofith longitudinal members curve downwardly and merge with the front and rear walls of transverse member l! and with the front wall of transverse member [4 in arcuate sections 21, 28, respectively. Preferably, the radii of all of the arcuate sections correspond to the width of the adjacent portions of the main members.

Throughout the rear portion of the chassis frame, both horizontal and upright webs are enlarged in thickness at points where stresses are increased as indicated for example at 30, 3|, 32, 33, 34, 35. Reenforcing ribs are formed integrally with the frame as indicated for example at 36, 31, 38, 39, 40.

The curved gussets and webs, the thickening of the webs at strategic points and the provision of additional reenforcing ribs where advisable make it possible to form a very rigid structure, without unnecessary thickness of metal where it is not required, which will withstand the bending moments and twisting which are applied to the frame during the operation of the crane irrespective of the shifting of the moments and torsional strains amounting to the loads on the crane and various positions of the swinging pull. This shaping and distribution of the metal in a one-piece casting not only makes it possible to eifect the desired results by using a minimum of metal for given load requirements, but avoids abrupt changes in sections, with resultant concentration of stresses, and avoids localization of stresses at corners, as where welding is resorted to or, alternately, expensive punching, drilling and riveting operations and, of course, the inefficient use of metal where overlapping plates and shapes are utilized to build up the frame, as has been the practice heretofore.

The provision of the necessary strength while using a minimum amount of metal minimizes the total load on the vehicle wheels and on the highway over which the crane is operated and makes for a greater safety factor for the highway than would be possible with the heavier frame required in a built-up structure.

Some of the features embodied in the preferred construction illustrated and described may be used without necessarily associating therewith the other features shown and described and the details of the structure may be modified substantially without departing from the spirit of the invention and the exclusive use of those modifications coming within the scope of the claims is contemplated.

What is claimed is:

1. In a motor crane chassis frame, main longitudinal members and transverse members of boxlike cross section of substantial width and depth and positioned at substantially the same general level with portions intersecting each other, the intersecting portions comprising upright arcuate webs, each having a radius corresponding generally to the width of the adjacent box-like portions of the members, and a turntable horizontal platform extending between the main longitudinal members intermediate said transverse members and having depending webs merging with said longitudinal members, said members, arcuate webs and platform being formed in a one piece metal casting.

2. In a motor crane chassis frame, main longitudinal members and transverse members at substantially the same general level, each member varying in width and depth between its ends, portions of the longitudinal members merging with the transverse members, at least one of said transverse members including a hollow box section projecting transversely of the chassis from the main longitudinal members and forming a housing below said level for slidably receiving frame-supporting outriggers, an integral horizontal turntable platform extending between the main longitudinal members and positioned between the main transverse members, all of said structure being formed in a one piece casting.

3. A motor crane chassis frame formed of a one piece casting and including main longitudinal members of box-like cross section varying in width and depth between their ends and a turntable platform which forms a portion of the top walls of said longitudinal members but projects outwardly from the outer side walls of said longitudinal members, and transverse vertical webs extending between and merging with the inner walls of said longitudinal members, and other transverse vertical webs extending outwardly from the outer side walls of the longitudinal members and merging therewith.

4. In a motor crane chassis frame, main longitudinal members of box-like cross section varying in width and depth between their ends, a turntable horizontal platform extending between said longitudinal members, there being box-like brackets formed integrally with and depending from the main longitudinal members beneath the turntable platform and provided with bearings for traction wheel mountings, all of said structure comprising a one piece metal casting,

5. In a motor crane chassis frame, main longitudinal members spaced apart and each having a box cross section, a transverse member extending between and outwardly from said longitudinal members and being of box cross section and lying in the same general plane as said longitudinal members but having a depth substantially greater than the depth of said longitudinal members, arcuate webs merging the inner and outer side walls of said longitudinal members with the side walls of said transverse member between the longitudinal members and outwardly of the longitudinal members, respectively, and arcuate webs merging the bottom walls of said longitudinal members with the lower portions of both side walls of said transverse member.

6. In a motor crane chassis frame, main longitudinal members of box-like cross section spaced apart, a turntable horizontal platform formed in part by the top walls of said members and extending therefrom across the space between said members, vertical webs between said members and merging therewith and with said platform, and box section extensions depending from said members below said platform and forming structure for mounting supporting wheel and axle structure, said members, platform, webs and extensions being formed in an integral cast metal unit.

7. A motor crane chassis frame comprising a unitary cast metal unit including a pair of spaced apart main longitudinal members, each of which has throughout a portion of its length relatively heavy box-like sections and throughout the remainder of its length has a relatively light single vertical web section, spaced apart main transverse members of box-like section connecting and extending outwardly from the relatively heavy box-like section portions of the longitudinal members, a turntable platform between said transverse members and extending between and merging with the box-like sections of the Iongitudinal members, axle mounting structure depending from said box-section portions of the longitudinal members below said platform and having bearings for mounting traction wheel and axle structure, said transverse members forming housings for retractable Outriggers, and elements on said relatively light portions of said heavy members for connecting the frame to supporting wheel and axle structure.

8. In a motor crane chassis frame, main longitudinal members and transverse members of boxlike cross section of substantial width and depth and positioned at substantially the same general level with portions intersecting each other, and a. turntable horizontal platform extending between the main longitudinal members at substantially the same general level, said members and platform being formed in a one piece metal casting.

9. In a motor crane chassis frame, main longitudinal members and a transverse member extending between and outwardly beyond said longitudinal members and being substantially hollow References Cited in the file 01 this patent UNITED STATES PATENTS Number Name Date 780,369 De Montgolfier Jan. 17, 1905 1,473,651 Smith Nov. 13, 1923 1,737,810 Tarbox Dec. 3, 1929 1,843,422 Henry Feb. 2, 1932 1,872,506 Sage Aug. 16, 1932 1,948,256 Cease Feb. 20, 1934 2,144,760 Hamischfeger Jan. 24, 1939 2,194,349 Almdale Mar. 19, 1940 

